Combadges were used for on-board ship communication with other Starfleet personnel when using the internal communication system was impossible or impractical, for accessing the on-board computer when not in an area that the computer is monitoring, for ship-to-shore communications, and for direct communication to another combadge. Combadges were configured to act as universal translators. (DS9: "For the Uniform"; VOY: "The Cloud", "The 37's", "Investigations") A Bajoran combadge is capable of recording logs such as that of the chief of security. (DS9: "The Ascent")

In TNG: "Future Imperfect" the combadge used in the false future comprised the delta shield and rectangular strips behind it signifying rank, doing away with rank pips; while in TNG: "Parallels" the same combadge was seen again alongside rank pips. The backing strips were colored either gold, silver, or black depending on the rank of the wearer; admiralty had a starred gold delta with silver backing strips.